What is Static Application Security Testing?

What is static application security testing (SAST)?

Static Application Security Testing (SAST) is a security testing methodology for applications that analyzes an application’s source code, bytecode, or binaries for vulnerabilities without executing the program. It helps developers identify and fix security flaws early in the Software Development Lifecycle (SDLC) before deployment.

How SAST Works

1. Scans Source Code – Examines code for security vulnerabilities, logic flaws, and compliance violations.
2. Identifies Common Security Issues – Detects issues like SQL injection, cross-site scripting (XSS), hardcoded credentials, and insecure coding practices.
3. Integrates into CI/CD Pipelines – Helps automate security checks during development to reduce risks before release.
4. Provides Fix Recommendations – Offers detailed reports and remediation guidance to developers.

Benefits of SAST

✔ Early Detection – Identifies vulnerabilities at the coding stage, reducing the cost of fixing security flaws later.
✔ Non-Intrusive – Does not require running the application, making it ideal for early-stage testing.
✔ Compliance Assurance – Helps meet security standards like OWASP Top 10, PCI-DSS, GDPR, and NIST.
✔ Developer-Friendly – Provides insights directly to developers, enabling secure coding practices.

Common SAST Tools

• SonarQube
• Checkmarx
• Fortify Static Code Analyzer
• Veracode Static Analysis
• Codacy

Example Use Case

A developer submits new code to a CI/CD pipeline, where SonarQube scans it and detects SQL injection vulnerabilities. The tool provides remediation steps, allowing the developer to fix the issue before deployment.

When to Use SAST?

• During software development to detect security flaws early.
• In DevSecOps workflows for continuous security integration.
• To ensure secure coding standards across development teams.

By incorporating SAST into the development process, organizations can proactively identify vulnerabilities, improve code security, and reduce risks before deployment.

What is the difference between static and dynamic application security testing?

Static and dynamic application security testing are two primary approaches to application security assessment. The key difference is that static testing analyzes code without executing it, while dynamic testing evaluates the application while it is running.

Static Application Security Testing (SAST)

SAST is a white-box testing method that examines an application’s source code, bytecode, or binaries to identify security vulnerabilities before execution.

Key Features of SAST

• Analyzes code without running the application.
• Identifies vulnerabilities early in development, reducing remediation costs.
• Detects coding flaws, such as SQL injection, cross-site scripting (XSS), and hardcoded credentials.
• Works best in CI/CD pipelines to enforce secure coding practices.
• Example Tools: SonarQube, Checkmarx, Fortify, Veracode

Example Use Case

A developer pushes new code to a repository. A SAST tool scans the source code and detects a hardcoded password, allowing the developer to fix the issue before deployment.

Dynamic Application Security Testing (DAST)

DAST is a black-box testing method that analyzes an application while it is running to detect real-world vulnerabilities.

Key Features of DAST

• Tests applications in a live environment, simulating real-world attacks.
• Identifies runtime security issues, such as authentication flaws, misconfigurations, and injection attacks.
• Finds vulnerabilities that SAST may miss, like improper session management.
• Works best during QA and staging before deployment.
• Example Tools: OWASP ZAP, Burp Suite, Acunetix, AppSpider

Example Use Case

A DAST tool is used to scan a deployed web application. It simulates a SQL injection attack on the login page and identifies a vulnerability that could be exploited by hackers.

Do You Need Both SAST and DAST?

Yes, using both SAST and DAST together provides comprehensive security coverage:

• SAST helps identify vulnerabilities early in development before code is deployed.
• DAST finds runtime vulnerabilities that SAST cannot detect.

By combining static and dynamic security testing, organizations can detect and mitigate security risks at every stage of the software development lifecycle (SDLC), leading to more secure applications.

Is static application security testing also known as black box testing?

No, SAST (Static Application Security Testing) is not considered black-box testing; it is actually a white-box testing method.

Why SAST is White-Box Testing

• SAST analyzes the internal structure of the application by reviewing its source code, bytecode, or binaries.
• It does not require the application to be running.
• Developers have full visibility into the code being tested.
• It is used early in the Software Development Lifecycle (SDLC) to detect vulnerabilities before deployment.

What is Black-Box Testing?

• Black-box testing (such as DAST) evaluates the application from an external perspective, without access to the source code.
• It tests the running application for security flaws, just like an attacker would.
• It is used to find runtime vulnerabilities like SQL injection, authentication flaws, and misconfigurations.

Conclusion

SAST is white-box testing, as it examines the internal code structure, whereas black-box testing (DAST) evaluates security from an external perspective. For a strong security strategy, both SAST and DAST should be used together.

What is the difference between software composition analysis (SCA) and static application security testing (SAST)?

Software Composition Analysis (SCA) and Static Application Security Testing (SAST) are both security testing methods, but they focus on different aspects of application security.

What is SCA (Software Composition Analysis)?

SCA is a security testing technique that analyzes open-source and third-party components in an application to identify vulnerabilities, license risks, and outdated dependencies.

Key Features of SCA

• Detects known vulnerabilities in open-source libraries and third-party dependencies.
• Checks compliance with open-source licenses to prevent legal risks.
• Identifies outdated components that may introduce security flaws.
• Uses vulnerability databases like CVE, NVD, and OWASP Dependency-Check.
• Example Tools: Snyk, WhiteSource, Black Duck, OWASP Dependency-Check

Example Use Case

An SCA tool scans an application and identifies that a third-party library, Log4j, has a critical security vulnerability (CVE-2021-44228). The tool alerts the development team to update or replace the library.

What is SAST (Static Application Security Testing)?

SAST is a security testing method that analyzes an application’s source code, bytecode, or binaries for security vulnerabilities without executing the program.

Key Features of SAST

• Scans proprietary source code to detect security flaws and insecure coding practices.
• Identifies vulnerabilities such as SQL injection, XSS, hardcoded secrets, and weak encryption.
• Integrates with CI/CD pipelines to prevent security issues early in development.
• Does not detect vulnerabilities in third-party dependencies (which is where SCA is needed).
• Example Tools: SonarQube, Checkmarx, Fortify, Veracode

Example Use Case

A SAST tool scans an application’s source code and detects a hardcoded API key, warning the developer to remove it before deployment.

Do You Need Both SCA and SAST?

Yes, SCA and SAST complement each other:

• SCA helps secure third-party dependencies that your application relies on.
• SAST helps secure your own proprietary code by detecting security flaws early.

For comprehensive application security, organizations should use both SCA and SAST together to detect vulnerabilities in both custom-written code and open-source components.